Evidence ledgerAvailable measures
Every card keeps the measure, year, method, and limitations attached to the number—or explains why no number is shown.
Source availableHLO scale points
World Bank Harmonized Learning Outcomes (HD.HCI.HLOS)
A cross-assessment harmonized learning score on the World Bank HLO scale; it is not an IQ score.
Method and limits
The World Bank links international and regional student assessments onto a common learning scale.
- Assessment years, tested grades, subjects, and coverage differ by country.
- Crosswalked achievement is not a direct measure of population IQ.
Uncertainty: No static numeric value is shipped until a release, country-year, and source row are pinned.
Source availablepercent
World Bank Learning Poverty: children unable to read and understand a simple text by age 10
The share below minimum reading proficiency, adjusted for children out of school; it is an education indicator, not IQ.
Method and limits
The World Bank combines minimum reading proficiency evidence with the share of primary-age children out of school.
- Reference years and assessment sources vary across countries.
- Modeling and out-of-school adjustment make this different from a single administered test.
Uncertainty: The atlas records the indicator definition but does not freeze a numeric estimate without its release-specific uncertainty and reference year.
Source availableHCI+ index points
World Bank Human Capital Index Plus (HCI+)
A 2026 human-capital context index spanning health, education, on-the-job learning, and economic participation; it is not IQ.
Method and limits
The World Bank combines health, education, employment, and on-the-job learning components with evidence-based weights.
- The index is designed for human-capital productivity context, not individual cognitive assessment.
- Country comparisons inherit differences and uncertainty in component data.
Uncertainty: No country score is copied until the 2026 release row and any revisions are captured in a versioned snapshot.
Source availablepercent
UNESCO UIS SDG 4 minimum proficiency in reading (end of primary)
The percentage of children or young people achieving at least minimum reading proficiency at the end of primary education.
Method and limits
UIS compiles country-reported and assessment-derived SDG 4 indicator data using internationally maintained metadata.
- Values may be observed, adjusted, modeled, or unavailable depending on the UIS series dimensions.
- Minimum proficiency is an educational benchmark and cannot be relabeled as national IQ.
Uncertainty: No static percentage is included without selecting the UIS sex, location, assessment, and reference-year dimensions.